1. Field of the Invention
The present invention is in the field of drywall tape applicators and systems, and in particular to an improved drywall tape and joint compound applicator system.
2. Discussion of the Related Art
It is common in the construction industry to use gypsum board drywall products in the finishing of interior walls and ceilings. A number of pieces of gypsum board will typically be attached with screws or nails to a frame backing in order to completely cover a wall. Eventually, the drywall will be finished by the application of paint, wallpaper or other texturing materials.
Prior to finishing the wall or ceiling any gaps, also known as joints or seams, between individual pieces of gypsum board are filled so that the wall or ceiling takes on the character of a single smooth surface. A typical method of finishing involves the application of a drywall joint compound to a seam, overlaying the compound with a drywall tape, and then applying additional compound over the tape. The tape is smoothed, and excess joint compound removed, by scraping the taped area with a hand trowel. After the compound has dried the surface is sanded to a smooth finish prior to final finishing with paint, wallpaper and the like.
While simple methods provide an advantage in minimizing the amount of equipment required to perform a drywall job, they nonetheless suffers from a number of limitations. For example, applying the correct amount of joint compound takes a significant degree of skill in order to avoid using too much or too little compound. Gaps in the application of compound are especially problematic as uncompounded tape will not adhere to the gypsum board, and will frequently lift away from the surface, or curl at the edges, creating an obvious imperfection on the wall or ceiling being finished.
Similarly, drawing the drywall tape by hand through a reservoir of joint compound can be awkward, especially for a user working alone. Such problems increase the time required to perform a drywall job, affect the consistency of the drywalling process, as well as adversely affect the aesthetic quality of finished walls and ceilings.
Consequently, various drywall tape application systems have been devised in order to simplify the drywall process and improve the consistency of the finished product. For example, U.S. Pat. No. 3,348,166 (Cavanaugh et al.) discloses an apparatus for feeding drywall tape through a container so as to enable a coating of joint compound to be applied to the tape.
U.S. Pat. No. 3,344,770 (Schaefer et al.) discloses an apparatus for dispensing a strip of material such as drywall tape, and which provides for attachment to a bucket containing an adhesive, and a squeegee device to regulate the amount of adhesive applied to the strip of material.
U.S. Pat. No. 4,367,692 (Underwood & Radtke) discloses a joint compound dispenser in which wallboard joint tape is coated with joint compound as the tape is drawn through a container of the compound, and then out an exit slot that regulates the amount of compound adhering to the tape. The device also permits the tape to be drawn upwardly for application to a wall, without causing the compound to be removed by the top edge of the exit slot.
U.S. Pat. No. 4,757,783 (Matheny) discloses a combined tape dispenser and joint compound container. Tape is drawn through the container, within which is a channel operative to dispense joint compound onto the tape as it is drawn through the container. An adjustable metering gate regulates the amount of compound retained on the tape.
U.S. Pat. No. 5,029,552 (Ovens) discloses a container attachment device for applying plaster or cement to a tape passing through a container of said plaster or cement. The device is an elongated housing that causes the tape to be passed through the plaster contained in a pail, and a blade to ensure an even thickness of plaster is applied to the tape before it leaves the pail.
U.S. Pat. No. 5,736,001 (Samuelson) discloses a combined joint compound hopper and tape dispenser. Compound is applied to the tape by drawing the tape through the joint compound contained in the hopper. Passing the tape through two pinch rollers removes excess compound, thus regulating the amount of compound adhering to the tape.
Although these prior art devices generally serve their purpose, they nonetheless each have limitations that affect their overall usefulness. For example, in many of these devices the container for the joint compound is separate from the drywall tape applicator. These containers may further be complicated devices that add to the cost of equipment needed to perform a drywall operation. Still others are devices that combine the tape dispensing and compound containing functions, requiring the transfer of compound from the container it is purchased or prepared in to the hopper of the dispensing device.
Still others are limited by the fact that tape cannot be pulled from the dispenser in a position above or below the joint compound-metering device without scraping off compound from one side of the drywall tape.
Thus, it would be desirable to have a drywall taping device that is easy to use, simple to manufacture and avoids problems associated with prior art devices.